Measuring ultrafine aerosols by direct photoionization and charge capture in continuous flow
Bibliographic record
Abstract
Direct ultraviolet (UV) photoionization enables electrical charging of aerosol nanoparticles without relying on the collision of particles and ions. In this work, a low-strength electric field is applied during particle photoionization to capture charge as it is photoemitted from the particles in continuous flow, yielding a novel electrical current measurement. As in conventional photocharging-based measurement devices, a distinct electrical current from the remaining photocharged particles is also measured downstream. The two distinct measured currents are proportional to the total photoelectrically active area of the particles. A three-dimensional numerical model for particle and ion (dis)charging and transport is evaluated by comparing simulations of integrated electric currents with those from charged soot particles and ions in an experimental photoionization chamber. The model and experiment show good quantitative agreement for a single empirical constant, KcI, over a range of particle sizes and concentrations providing confidence in the theoretical equations and numerical method used. Copyright © 2018 American Association for Aerosol Research
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How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.001 |
| Science and technology studies | 0.000 | 0.001 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.000 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one teacher head, not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".